Objective-C, the language used for developing applications to run on Apple's mobile devices, was ranked the third most-popular language in the July edition of the Tiobe Programming Community Index, followed by C++ in fourth place. Released this week, the index has Objective-C used by 9.335 percent of developers and C++ used by 9.118 percent. The two languages swap rankings from last month, when C++ was used by 9.358 percent of developers and Objective-C by 9.094 percent.

"Right from the beginning, Objective-C and C++ competed to become the de facto object-oriented programming language," Tiobe said in its monthly report. "It took quite some years before C++ could claim victory. Now Objective-C is back (thanks to the iPhone and iPad), but not as a direct competitor of C++ any more. C++ is used heavily in large high-performance systems, whereas Objective-C is mainly used in the mobile apps industry."

Tiobe's ratings are based on number of skilled engineers, courses, and third-party vendors leveraging a particular language, with rankings determined by assessments of popular search engines like Google, Bing, and Yahoo. Analyses of other sites, such as Wikipedia, Amazon, and YouTube, also are factored into the assessment. C maintained the top spot in this month's index, used by 18.331 percent of developers, while Java again comes in second place, used by 16.087 percent of developers. Rounding out the top 10 were C#, in fifth place (6.668 percent), followed in succession by (Visual) Basic (5.695 percent), PHP (5.012 percent), Python (4 percent), Perl (2.053 percent), and Ruby (1.768 percent).